Investments In Unconsolidated Entities (Summarized Balance Sheet Financial Information Of Investments In Unconsolidated Affiliates) (Detail) (USD $) In Thousands, unless otherwise specified	Jul. 31, 2012	Apr. 30, 2012
Schedule of Equity Method Investments [Line Items]
Current assets	$ 13,616	$ 17,513
Noncurrent assets	33,926	34,597
Current liabilities	12,400	12,815
Noncurrent liabilities	$ 5,361	$ 5,382

The amount of current assets reported by an equity method investment of the entity.

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+ Details

- Definition

The amount of current liabilities reported by an equity method investment of the entity.

+ References

+ Details

- Definition

The amount of noncurrent assets reported by an equity method investment of the entity.

+ References

+ Details

- Definition

The amount of noncurrent liabilities reported by an equity method investment of the entity.

+ References

+ Details